|
|
The little things add up. Few of us stop to think about the environmental impact when we turn on a light or launder a load of clothes. But with millions of other people doing the same thing, such simple actions have a surprisingly large cumulative impact.
Fossil fuels contribute to global warming. Much of the energy we use in our homes is created by burning carbon-based fuels, including oil, natural gas, coal, and biomass (derived from timber, agriculture, and food processing waste). That produces carbon dioxide, the primary greenhouse gas. Greenhouse gases, whether spewing from tailpipes or power plants, trap heat near the Earth, resulting in the climate changes collectively referred to as global warming. Depending on where you live, you may have limited control over the type of energy you use in your home. However, you could have more control than you realize over how much of it you use.
Fossil fuels are also a finite, nonrenewable resource. Experts predict that we have 20 to 100 years before worldwide demand for petroleum will exhaust available supplies.
Brownouts (when electrical power is reduced) and blackouts (when electrical power fails) are becoming more frequent. That makes energy conservation increasingly important, especially during peak periods of demand. Electric power outages cost the nation $80 billion annually, according to researchers from Lawrence Berkeley National Laboratory. A number of factors, including an aging infrastructure, and in many states, utility deregulation, have combined to make the national electric grid more vulnerable to breakdown. However, individuals can make it better or worse by how much air conditioning and other appliances they use during periods of peak demand, such as heat waves. More information on the stability of our nation’s power grid is available at the Department of Energy Web site.
Generating electricity produces more air pollution than any other industry in the U.S. Some power-plant fuels burn more cleanly than others, resulting in lower emissions. Natural gas burns the cleanest, coal pollutes the most, and oil is somewhere in between. Coal-fired plants produce chemicals, such as sulfur dioxides and nitrogen oxides, and particulate matter (or fine particles) that cause smog and acid rain. This fine particulate matter mixes together with other chemicals and can exacerbate asthma and other respiratory diseases. Mercury is also released by coal-fired plants and goes into the air before settling into the soil and water. You can learn more about mercury by visiting our toxics directory and search for mercury. Methyl mercury, a very toxic form of mercury, builds up in the food chain, particularly in fish, including many of the ones we eat.
Air pollution is also created at an earlier stage in the energy-production process, when fossil fuels are extracted from the earth and processed, such as at oil refineries.
Power plants produce other waste that must be disposed. Nuclear power plants generate extremely toxic waste that remains radioactive for tens of thousands of years. The total amount of spent nuclear fuel in the U.S. currently exceeds 40,000 metric tons, which is stored at about 70 sites around the country. That volume is expected to reach 60,000 metric tons by 2010.
Conventional fossil-fuel powered plants (oil-, coal-, or natural-gas-burning plants) generate waste ash that contains toxic chemicals and must be disposed of in specially designed landfills.
While wind and solar power generate little waste, the photovoltaic cells and batteries that may be part of a solar array can contain some toxic substances such as cadmium, which can be a problem if it ends up in a landfill. You can learn more about cadmium toxicity by searching our toxics directory. These batteries, however, can be recycled at the end of their useful life.
Waterways and wildlife are also affected by power generation. Many power plants work by converting water into steam to run turbines. The removal of water from local streams, rivers, and lakes can have a harmful effect on fish and other aquatic life as can the discharge of used water that may be too hot or too cold.
|
|
|
